


Summer day

by Ticigi



Series: HP Kinkuary [1]
Category: Harry Potter - J. K. Rowling
Genre: Blackcest (Harry Potter), Established Relationship, HP Kinkuary 2021, Implied/Referenced Underage Sex, Incest, M/M, Office Sex, Plot What Plot/Porn Without Plot, Praise Kink, Sibling Incest
Language: English
Status: Completed
Published: 2021-02-02
Updated: 2021-02-02
Packaged: 2021-03-12 22:54:27
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 2,787
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29143305
Author URL: https://archiveofourown.org/users/Ticigi/pseuds/Ticigi
Summary: Sirius summons Regulus to his study.
Relationships: Regulus Black/Sirius Black
Series: HP Kinkuary [1]
Series URL: https://archiveofourown.org/series/2140914
Comments: 8
Kudos: 57
Collections: HP Kinkuary 2021





	Summer day

**Author's Note:**

> Written for HP Kinkuary
> 
> Prompt: Praise kink
> 
> There's referenced underage sex, but at the time the story is set, they're both adults.

Regulus began to shift on his lap. Sirius, frustrated with the generous pile of work over his desk still untouched, had summoned his brother about half an hour before, taking the opportunity after his father left. Orion didn’t trust him to not run away from his delegated share, so he was trapped inside the study by a timed spell until at least the next hour and Kreacher had strict orders not to side aparate him – so, instead of going to his brother, his little one came to him.

“Tired of waiting?” Sirius inquired as he put the open parchment he was holding over the desk.

“I told you, we’re not doing anything until you finish your work. If I let you do as you wish, you’ll blame me for distracting you and I’ll be the one reprimanded.” Regulus retorted, crossing his arms.

Truth was, having Regulus sat on his lap was considerably slowing his work, – that now consisted of reading contracts, as it was more convenient to their current arrangement – his crotch was being lightly pressed under the weight of a tight as his brother was placed sideways with his knees over the comfortable arm of the chair, feet bouncing slightly and a little room left at the seat for his arse pressing at Sirius’s side. This was an old argument between them; whilst their parents feigned ignorance over the exchanged glances at the dinner table, at Sirius openly planting kisses on his brother’s forehead in their presence or at the light steps on the hallway deep into the night in their visits to each other's bedrooms, they were both under rigid expectations regarding their duties. As long as Sirius maintained everything relatively sorted in their business, and did nothing in public that’d be an embarrassment to the Blacks, mother dearest wouldn’t expel him for corrupting her younger son. 

“How come you obey my order to sit on my lap, and refuse anything else? You were doing so well, being so good all day, until now.” Yes, Regulus had woken up particularly eager to please that morning, yielding to every little order Sirius gave him. 

A light shade of pink tinted Regulus’s cheeks. Sirius, knowing his brother better than anyone, took the reaction as a cue and placed an arm over Regulus’s form, pressing him to his chest. The younger man let his head rest over his brother’s shoulder, and Sirius could smell the faintest scent of lavender soap, almost completely gone, from their bath together a couple hours earlier. It was a particularly warm day, where, aside from cooling charms, baths were a relief – and Regulus enjoyed leaning on his chest in the bathtub. 

“As I said,” Regulus muttered against his neck, hot breath only contributing to his arousal, “you must finish your work first; otherwise you’ll put the fault on me for your procrastination.” He felt a peck on the same spot. God, Reggie could be so sweet even when he was being a brat. “Get your priorities done. Then we can move on.”

Sirius took hold of his brother’s jaw and turned his head firmly to meet his gaze. “Who says you get to give me an order? And who says a bunch of parchments are my priority when I have my boy needing my attention?”

His little one looked away. “I’m not–”

“You’re inquiet,” Sirius let go of him and placed his hand further down, touching what was the first signs of an erection, “and your cock says otherwise.” 

“But–"

“Quiet, Regulus, cease all this questioning. I’ll finish later.” At the stare his brother gave him, shiny grey orbs quietly pleading, Sirius relented. “Promise I won’t put the blame on you.” As if to seal his promise, he planted a chaste kiss on his brother’s temple. “Now, get on your knees and put your sweet mouth to work. Get my cock ready for you.”

With a nod, Regulus left his place on his lap and slid to the floor, the view of his body mostly obstructed by the mahogany desk. Opening his trousers and taking his half hard cock out of his briefs, the younger man wrapped long, thin fingers around his length and began stroking a couple of times; then, lowering his head and darting his tongue out to lap from the underside of the base until the tip, Regulus traced a long, thick vein along the way, when Sirius groaned and slid his fingers over dark hair, gently taking hold of the man on his knees, as his cock began to fill and the hot tongue tracing the length of his cock continued its path, diligently from the base to the tip all around his girth, making sure he was all covered in wetness.

His hold of Regulus's hair got stronger when he felt a moist mouth closing around the head, going down until he felt the tip reaching the back of Regulus’s throat as his shaft was growing longer and ticker inside the warm wetness. His eyes bore into Regulus, that, as if predicting his gaze, was already looking up at him from under his lashes, mouth full of cock.

Regulus’s head was bobbing as he kept sucking, not quite taking all his length yet, until Sirius was fully hard and firmly pressed his brother’s head down, letting out a moan when he was down to the root. 

A long, wanton sound vibrated around his cock, and Sirius couldn’t refrain from thrusting his hips up, with Regulus still drawing out his moans as he kept taking Sirius down, the tip of his nose occasionally pressing a nest of groomed dark hair at the base.

“You’re such a good boy, Reg, so good at it. Couldn’t have anyone better at sucking my cock.” Truth was, contrary to the rumours that preceded the older Black brother, Sirius wasn’t one to fool around and had very limited experience from before his relationship with Regulus; but he didn’t need to have a vast list of people that went down on him to know he’d choose Regulus any day. 

At this point, Regulus let out a choking sound and drawed his head back, until only the head remained in his mouth. He was flushing, and Sirius noticed how one of his hands moved from the floor, where he was supporting himself, down to where Sirius' eyes couldn’t reach under the table, probably to stroke himself.

Regulus began sucking and licking eagerly at the tip as he recovered his breath, Sirius’s mind a haze and the muscles of hs tights contracting with the feeling of wet kisses being pressed over the slit, the lickings and sucklings all around, until he was back inside, down on his brother’s throat, panting as he began thrusting again and hearing wet sounds and Regulus’s moans being cutted by his cock pounding in and out. 

He stared down again, taking the image of Regulus’s teary eyes looking up at him, his flushed cheeks, his lips red and plump closed around his girth, and Sirius decided it was enough; he needed to take Regulus before coming. Still keeping a firm hold on Regulus's soft waves, he pulled back, his cock coming out with a soft pop; there was precum beginning to leak at the slit, so he held himself at the base and brushed his cock clean on Regulus’s cheeks, ready to move on. 

“Now get up, strip, lean down the table and spread your legs so I can get you ready for me.”

He took his wand from the table as Regulus hastily stripped himself naked, rustling fabrics being thrown over a sofa near the window, and lowered his chest down to the desk, hands holding his arse to expose himself as Sirius turned to him and muttered a spell that filled his hole with lube, a small leaking amount tracing a path out of his entrance, glistening under the light. 

Sirius stripped out of his clothes, carelessly letting them pool on the floor before leaning down to place a kiss on the back of his neck as a reward. “So obedient. Keep behaving well, and I'll prepare you a nice and warm bath later and we’ll cuddle in my bed tonight." 

"I'll be good to you, Siri," his brother purred.

Still leaning down over Regulus’s back, he pressed a finger over the slick entrance and made his way in, moving his finger in and out until he deemed enough for a second one, slowly pushing it inside, the generous amount of lube making the path easier.

Regulus arched his back under him as he began opening him up with scissoring movements, letting out short breaths, hips grinding at the table to create friction over his cock pressed between his lower stomach and the polished, cold surface. “Siri,” he moaned, “please, faster,” he pleaded. 

Sirius drew close to his ear, fingers still working at the same rhythm inside Regulus, before whispering. “Patience, little one, don’t want to hurt you.”

Regulus pushed his hips back on Sirius’s fingers. “Need you, please.”

Sirius, with his free hand, tucked the strands of hair falling over Regulus’s flushed cheek behind his ear and planted a kiss there. “I know you do, but I have to take care of you; be good and let me finish prepping you properly.” He rebuked, finally adding a third finger in.

But Regulus still hasn't given up. He lifted his chest, supporting himself on his elbows and turned his head to lock gazes with Sirius, eyes half-lidded and cheek nearly imperceptibly marked with the bit of precum Sirius left there. “You can stretch me open with your cock,” he provoked with a lilting tone.

Fuck. Sirius felt his cock pulse with need, but he knew better than to relent. Especially since he had committed the mistake of hurting Regulus before for rushing things, on one of their first times, back when they were inexperienced students breaking curfew to meet in cold alcoves at Hogwarts. It was under Regulus’s insistent request, but Sirius never managed to fully forgive himself for caving in after the sight of his baby brother’s tear-stained cheeks rushing to hide on his chest as he tried to soothe the hurt.

So, deciding on maintaining a firm, commanding façade, he withdrew his fingers to mark Regulus’s round arse cheeks red as a warning, before diligently going back to his task of making room for himself. “Shut up, Regulus, or I’ll leave you here, stretched open and ready and forbid you from touching yourself.”

By the way his fingers were squeezed, Sirius figured it might not be as much of a punishment as he would think. He made a mental note to explore the hint at a posterior time. 

When he deemed enough, Sirius took his fingers out, conjured more lube to coat around his shaft, stroking himself a few times and pressed the head of his cock over Regulus’s puckered entrance, sliding up and down on his rim, teasing the moaning mess under him. He grinded the slick head against the back of Regulus’s balls, spreading lube along the way before finally going back up to his entrance and pressing himself inside, sliding slowly through the hot pressure surrounding his shaft until bottoming. Regulus let out a long cry as he carefully began the first thrustings, cock pressing the tight walls around him open, careful about giving enough time for Regulus to get comfortable before moving on. 

Feeling it was safe enough, his thrusts began to grow faster and longer, Regulus’s pantings mixing with the sounds of his balls and tights slapping against his plump arse. 

He closed his arms over Regulus’s torso and lifted his back against his chest, biting playfully on his neck and breathing praises against his ear as his hips pounded hard into him. He loved the way his little one’s slightlest tremblings and moanings whenever he whispered words of praise to him.

“You feel so good, so hot and tight around me,” Regulus drew a long, wanton moan at the words, hot over the shell of his ear “perfect little Regulus,” Sirius cooed, “so pretty moaning for my cock.”

Sirius kept thrusting at full speed, feeling the little droplets of sweat forming on Regulus’s back pressed against his chest, until he decided to change to a more comfortable set. The edge of the desk surely wasn't very gentle to Regulus’s sensitive skin, and his baby brother was not one to warn him on such occasions. 

“Turn around,” he commanded, taking his cock out and letting go of his hold on Regulus’s chest. As much as he enjoyed pounding Regulus from behind, it didn’t compare to the experience of watching Reg’s pale face flushed with a lovely shade of pink, his swollen lips round around low, soft moans, his grey eyes watering when he was close to completion. The strands of black hair all tousled from his earlier grasp. 

Regulus was a beautiful sight that he couldn't get enough of.

Facing his brother, he aided him to sit over the desk before thrusting back in, pounding a few more times before, once again, lifting the smaller body before him, his cock deep inside as Regulus’s thin legs and arms wrapped around him and moved to sit back on the armchair with Regulus straddled on his lap. 

“Now, be a good boy and fuck youself on my cock.”

Regulus placed his hands over Sirius’s shoulders for support and did as he was told, hips moving up and down and occasionally, when down to the root, wiggling around the thick cock.

“Fuck,” Sirius groaned after a while; deciding to take charge, he firmly held Regulus’s hips still and began slaming into the tight heat, feeling as a pair of trembling tights pressed tightly around his sides, and Regulus let his head fall down next to his, a few strands of hair, damp with sweat, brushed against his cheek. They kept the same fast, hard pace. Looking down, Sirius caught the sight of Regulus’s cock, slit moist with precum occasionally rubbing against his stomach as his brother’s chest leaned closer.

“Think you can come just from my cock?”

“Yes, Siri, almost there,” Regulus replied, getting closer to his ear, his nails carving crescents on Sirius’s skin. “But want to feel your cum in me first,” he completed in a near whisper, voice laced with urgent want.

Sirius felt himself pulsing inside him. God, Regulus knew how to turn him into a mess. He pounded even faster, feeling a pool of heat forming in his lower stomach as his cock got impossibly stiff. “Don’t worry baby,” he replied in between pants, “will stuff you full with cum.”

He heard a approving moan as he kept the same fast pace, both with short breaths and sweat forming at their foreheads, Regulus letting his head fall back as he let out little cries; eventually Sirius stiffened and, grabbing tighter on his brother’s hips, spilled his load, moaning at the impossibly tight clenching around his cock, thrusting a few more times after to milk everything inside.

Regulus, at the feeling of the hot seed splashing into him, got the mind-numbing feeling of his own orgasm on its way. “Sirius, I –” but it was late, a half-warning was all that passed through his lips, and soon there were stripes of his cum over their stomachs as Sirius bottomed in him. 

Sirius eventually withdrew, the absence of his cock allowing the wet feeling of come sliding out of Regulus’s entrance. If it was up to him, he’d keep stuffed with cock until Sirius was completely soft, but he knew how much his brother disliked being overstimulated. He let his head loll to rest on his big brother’s shoulder, tired and satisfied. “Hmm, love when we come at the same time.” 

He heard his brother chuckle, and felt a gentle hand petting his head. “Yeah, me too baby boy. You did really good today.”

It was a hot summer afternoon, the final sunset lights invading the room with their deep golden shine through the open curtains along with the furniture projecting longer shadows announcing the end of a solar day, and now that they were finished, the hot temperature as well as the droplets of sweat and soon-to-be drying cum over his belly were finally beginning to become a bother, making him crave that promised bath with Sirius; regardless, Regulus let his eyes close and went completely limp on his brother's lap, feeling as gentle arms surrounded his back to give him stability. He might complain and make things difficult sometimes, but in the end, he loved being a good boy to Sirius, and he knew his brother would always take care of him.

**Author's Note:**

> This was probably the fastest I've ever finish a fanfic, but I set myself the challenge of finishing the first prompt on the first day, so I feel maybe it's a bit rushed. I don't know how much better I could do while keeping my set date, though, but if you have any critique to make, as well as if you spot any grammar mistake, feel free to let me know.


End file.
